Everyone’s been in the position where there’s a million and one things going on, but a client (or you) still requires top-notch keyword research. So something needs to get done in a pinch. Searching around the internet and learning more about the trendiest aspects of keyword research (because let’s face it, either it’s been a while since you last did it or it’s your first time doing it) can take a ton of time. There are literally millions of things you could be reading about it; actually 15.4 million if we want to be precise.
Original post here https://moz.com/blog/keyword-research-in-90-minutes